A Congressionally ordered study of global warming and Western water resources was issued 25 April, and the Interior Department officials are calling it the first of its kind. This 226 page study authorized in 2009 covers eight Western water basins in the US. The basins are served by the Colorado, Missouri, and Columbia rivers.

Global warming will likely have a negative effect to salmon habitats in the northwest United States. The report has suggested that snow will melt sooner, causing floods that will hurt fisheries. Rain will replace snow altogether in some places. As temperatures rise, surface and groundwater will be harder to find. Salmon habitats will shrink as a result of these floods and invasive species could take hold in our rivers more easily.

These changes pose a significant challenge and risk to adequate water supplies," stated Mike Connor, head of the U.S. Bureau of Reclamation.

This study is unique because unlike others it covers all the Western water basins that the Bureau of Reclamation serves, operating dams, canals, and power plants in 17 Western states. Through the 21st century the study expects a 5 to 6 degree Fahrenheit temperature rise. The federal scientists, however, wish not to point the finger at anyone for the cause of global warming.

There's already a lot of data out there," Mike Connor shared in an interview. "This reaffirms a lot of what we already know."

In the California Central Valley there was an average 3 degree F. temperature increase through the course of the 20th century. In Washington State’s Columbia River Basin there was a 2 degree F. temperature increase.

In areas like the California Sacramento-San Joaquin Delta, a rise in temperature and water flow could hurt the dying Delta Smelt fish, jeopardize key salmon runs, and cause invasive species like the quagga mussel to become more plentiful.